A novel method for improving arc cooling in high-voltage gas circuit breakers

Plasma cooling is a key process for the successful operation of gas circuit breakers, which are devices that interrupt high-voltage arcs in power systems. Plasma cooling involves the decrease of the temperature and density of the plasma arc due to various physical and chemical mechanisms, such as radiation, conduction, and recombination. These mechanisms are strongly influenced by the turbulence level of the gas flow that surrounds the plasma arc, as turbulence enhances the heat and mass transfer between the plasma and the gas, as well as the chemical reactions that consume the plasma species. Therefore, controlling the turbulence of the gas flow can be an effective way to improve the plasma cooling performance and the dielectric recovery of the gas circuit breaker. In this paper, we propose a novel method for turbulence control based on a constant flap attached to the contact geometry. The flap modifies the pressure distribution in the nozzle and generates streamwise vortices that affect the turbulence and heat transfer of the flow. We investigate the effect of the flap on the plasma cooling rate and the flow field aerodynamics by using numerical methods. We compare the results with and without the flap and analyze the impact of the flap on the plasma cooling mechanisms and the gas flow characteristics.